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The effect of ␥-Al 2 O 3 nanopowder electrolyte concentration and rotation rate on copper reduction from sulfuric acid electrolytes was examined with rotating disk electrodes. Regions of copper inhibition and enhancement were identified in the kinetic regime, with little change in the mass-transport copper limiting current density. Low particle electrolyte concentration ͑12.5 g/L͒ resulted in an inhibited copper rate, while high particle concentration ͑60 g/L͒ inhibited the rate at low overpotentials and accelerated it at higher overpotentials, depending on the electrode rotation rate. Scanning electron microscopy ͑SEM͒ analysis does not support a correlation between the observed inhibition and enhancement with microstructural surface area.

Section: Resultsmentioning

confidence: 99%

The Effect of Al[sub 2]O[sub 3] Nanopowder on Cu Electrodeposition

Lozano-Morales

Podlaha

2004

“…11 for i Յ i pϭ1 gives [14] For i > i pϭ1 , c p,s ϭ 0 and from Eq. 11 we see that the volume fraction of particles in the film is inversely proportional to the deposition current density [15] Equations 14 and 15 are general expressions for the volume fraction of particles incorporated into a growing film. The volume fraction is dependent on the charge on the metal ion (z), the molar volume of the deposited metal (V m,M ), the particle radius (r), the diffusion coef- We note that the diffusion layer thickness for particles is considerably smaller than the diffusion layer thickness for ions in solution due to the difference in diffusion coefficients.…”

Section: Figurementioning

confidence: 92%

“…Various models have been proposed that take into account these effects. [9][10][11][12][13][14][15] In this paper we show that the deposition of nanocomposite Ni/Al 2 O 3 films can be described by a model taking into account the convective diffusion of particles to the growing surface and adsorption of the particles at the interface.…”

mentioning

confidence: 91%

Particle Codeposition in Nanocomposite Films

Vereecken

Shao

Searson

2000

112

Nanocomposite films can be deposited by electrochemical deposition of a material from a solution containing a suspension of nanometer size particles. We show that the kinetics of nanometer size particle incorporation into a growing film can be described by a model that takes into account the convective diffusion of particles to the surface and treats particle incorporation in terms of the residence time at the surface. Experimentally, particle transport can be controlled using a rotating disk electrode. We show that incorporation of 300 nm Al 2 O 3 particles into nickel films can be described by this model.

“…As a result, metal matrix composite coatings are formed by incorporation of the particles in the coating during electrodeposition. During the past decades, the electrolytic deposition of such dispersion coatings has become an important industrial technology with applications such as wear resistance [2][3][4][5][6] and corrosion resistance. 7,8 Other, more recent applications include thermal regulation and thermal actuation by codeposition of phase change materials, 9,10 selflubricating coatings containing oil microcapsules 11 and permanent hydrophobicity.…”

mentioning

confidence: 99%

The Effect of Surface Charge on the Deposition Rate of Particles with Metals

Soccol

Ntumba-Ngoy

Claessens

et al. 2014

The influence of ζ-potential on the electrodeposition of particles with metals was investigated by the codeposition of three different types of particles (BaSO 4 , CaF 2 and K 1.33 Mn 8 O 16 ) with three different metals (nickel, copper and zinc) from seven different, unsupported (binary) and well-supported plating solutions across the whole pH range. The surface charge of the particles in the plating solutions was modified by adding potential determining ions that are electrochemically silent. The surface charging behavior of the different particles was determined in indifferent electrolytes and in diluted plating baths. In all cases, making the surface potential more positive increased the deposition rate of particles, while if the surface charge is reduced or made negative, the deposition rate of particles decreased. By comparing the magnitudes of the different forces acting on particles and how they are affected by changes in the surface charge of the particles, we conclude that the change in the codeposition are due to either a change in the mass transport of particles by the electrophoretic force or a change in the particle-electrode adhesion due to the double layer force.Electrodeposition of metals and alloys allows easy control over coating thickness and morphology, but the coating properties are restricted to those of the deposited metals. 1 To improve or add specific properties to the coating, particles can be added to the plating bath. As a result, metal matrix composite coatings are formed by incorporation of the particles in the coating during electrodeposition. During the past decades, the electrolytic deposition of such dispersion coatings has become an important industrial technology with applications such as wear resistance 2-6 and corrosion resistance. 7,8 Other, more recent applications include thermal regulation and thermal actuation by codeposition of phase change materials, 9,10 selflubricating coatings containing oil microcapsules 11 and permanent hydrophobicity. 12 The extent to which particles modify the coating properties is determined, to first order, by the amount of particles that are incorporated into the metal. Contrary to what one might expect, the amount of codeposited particles is often disappointingly low (below 1 vol%) despite the fact that particle concentrations of 100 g/L or more are used. Hence, ways have been sought to increase the rate of particle deposition and to understand why in some cases, the codeposition rate is so low.In the past, it was shown that the hydrophobicity and the surface conductivity of particles strongly influences their incorporation during electrodeposition. 13-16 Also the sign and magnitude of the particle surface charge has been mentioned as an important factor and various authors believe that a positive surface charge aids codeposition. [17][18][19][20] During electroplating, the cathode is polarized negatively. Thus it is not surprising that people believed that positively charged particles would be electrophoretically or electrostatically attra...